(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A ball is tied to an elastic string of length 8.0m and swung in a horizontal circle with a velocity if 0.8m/s. When a metallic object is tied to a rope of length 2.75m and swung in a horizontal circle, it makes 1 revolution in 2.9s. The ratio of the centripetal force in the rope is 1/3. Find the mass of the metallic object attached to the rope, if centripetal force in the string is 0.20 N.

given: r1:8m

v1: .8m/s

r2: 2.75m

T: 2.9s

F: .2*(1/3)=1/15

2. Relevant equations

F=ma(c)=m*(v^2/r)

v=2∏r/T

3. The attempt at a solution

v=2∏(2.75)/2.9m=5.96

a=v^2/r=5.96^2/2.75=12.92m/s^2

F=ma(c)=(1/15)/12.92=.5g

but like i didnt use the values of radius 1 and velocity 1 so something must be wrong, and like .5g for a metallic object isn't that a little bit too lite? thanks for help anyways, i appreciate all topic related answers

P.S. thats due on this friday so please i need it quick please please please.

1. The problem statement, all variables and given/known data

2. Relevant equations

3. The attempt at a solution

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# Homework Help: Torque, mass has to be found with centripetal force

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